Consumers Cultivating The Pearl

March 31, 1985|By Martha Gross, Staff Writer

The newest rage in precious jewelry is the creation of a mussel, cultivated in a Japanese lake. It`s a freshwater pearl.

Top-drawer jewelry houses such as Bulgari report an upsurge in sales. Saks Fifth Avenue has been giving freshwater pearls a big push during the past six months and features the collections of Didi Boring, head of Boring and Co. of San Francisco, which stocks one of the largest inventories of freshwater pearls in the country. Gump`s, the San Francisco-based specialty chain, reports as much business in freshwater pearls this year as in cultured pearls.

Freshwater pearls, although they share some of the characteristics of cultured pearls, vary in size, shape and origin.

Most people think of pearls as the round, symmetrical, white or rose-colored products of oysters. Freshwater pearls are rarely round. They are shaped like pebbles, beans, rice, crosses or hearts; they come in irregular shapes that nature`s whimsy dictates. And their colors reflect the tints that light an opalescent sky at dusk: pink, soft gray, iridescent blue, silver-violet, pale salmon and whipped-cream white.

They are real pearls, although they are grown in mollusks -- rather than oysters -- that live in rivers and lakes. Freshwater pearls sometimes are called Biwa pearls because most, and those of the best quality, are grown in Japan`s Lake Biwa, near Kyoto.

Many mollusks can grow pearls. But what they grow may be without luster, or a dull white or reddish shade. Only those mollusks that produce nacre, a pearly substance, can make pearls as we know them.

To prod a mollusk to make a pearl, a bit of foreign material, called an irritant, is inserted into a mother mollusk, forming a pearl sac around it. The sac secretes nacre around the irritant and over a period of time -- about three years for good quality -- the layers of secretions build up to form a pearl.

Natural pearls are formed the same way when foreign substance finds its way into the mollusk without human assistance.

For cultured oriental pearls, the irritants are small mother-of-pearl beads and tiny pieces of mussel tissue called mantle, which are planted in oysters that are returned to seawater. For freshwater pearls, the irritants are bits of mantle taken from a donor mussel. The shape of the pearl is determined by the shape of the irritant and its position inside the mother mussel. The color of the pearls depends on the genus and species of the mother and donor mussels.

Freshwater pearls may be the newest of wonders to some, but they have been around for a long time.

Freshwater pearling was a thriving industry in China 2000 years before Christ. Thirty-three centuries later, the Chinese discovered they could cultivate freshwater pearls in mussels by inducing irritants. Mud, wood, stone and metal were used. Small pearl statues of Buddha were produced by inserting tiny carvings into mother mussels.

Both freshwater and oriental pearls were in demand in medieval Europe. Later, the oriental pearls were more esteemed and plentiful, but the freshwater pearls still adorned royalty and gentry. A beautiful, oversized freshwater pearl was set in one of Queen Victoria`s crowns.

The Japanese got into the act at Lake Biwa about the turn of this century. In 1924, they made a breakthrough in successful cultivation procedures, and were a commercially viable freshwater pearl producer and exporter by the `30s.

Until recently, the regular shape of the round cultured or natural pearl was prized over the irregular or baroque. But no more. The irregular freshwater pearl is now having its day.

Boring said she saw her first really impressive freshwater pearl jewelry at a Gump`s counter 12 years ago. ``It was a necklace in bronze pearls with bluish highlights,`` she said. The designer was intrigued by the possibilities. Five years ago she set up the first company in the United States specializing in freshwater pearls.

Since then, she has watched their popularity zoom. She said she thinks their current popularity is more than a passing fad. ``Until now, people haven`t had a chance to see all the finer kinds of Biwa pearls. The`ve been accustomed to thinking of perfect roundness as a standard for `geminess.` But now they are seeing their beauty, and the wide range of Biwa colors and shapes available, and how they can be worked with other jewels.``

Boring thinks the freshwater pearl business will build momentum for commercial reasons. ``Usually, you can only grow one pearl in an oyster and when you harvest that pearl, the oyster dies. In a moderate-size mussel you can insert 20 irritants on each side and harvest 40 pearls. And then the mussel doesn`t die. You can have a second, even a third harvest, although the last pearls will not be as good.``

Cultivated freshwater pearls are being produced outside of Lake Biwa. ``They are being produced in other places,`` Boring said. ``China has a sizable production. The American Pearl Co. in Tennessee has for many years controlled the largest number of American natural freshwater pearls. With a Japanese partner, the company has been cultivating the pearls for the last several years, but their production is not large. Curiously, the pig-toe mussels -- the mussels that supply the bead centers for Japan`s cultured pearls -- come from this country, from the Mississippi River.``